Which of the following are advantages to simulation? I. Time compression
II. What-if questions are possible
III. Flexibility
IV. Trial and Error approach
V. Input must be user generated

A) I, III, V
B) I, II, V
C) II, III, IV, V
D) I, II, IV, V
E) I, II, III

Simulation offers several advantages, including time compression (allowing processes to be observed in a shorter timeframe), the ability to ask "what-if" questions to explore different scenarios, and flexibility in terms of adjusting parameters and conditions. The requirement that input must be user-generated is not necessarily an advantage; it's more of a characteristic or requirement of many simulations.